Rolling door assemblies, such as mini-warehouse doors, commercial rolling steel doors, and the like, are very well known in the art.
These rolling door assemblies typically comprise an overhead shaft which is mounted onto a fixed structure, such as a wall for example, a drum mounted about the overhead shaft, and a door curtain foldable (i.e. wound, coiled-up, etc.) about the drum and unfoldable from the same via a rotation of the drum so as to alternatively lower and raise the curtain, i.e. operate the door. Generally, these rolling door assemblies also generally comprise at least one, but typically a pair of, counterbalancing spring(s) having ends operatively connected to corresponding parts of the assembly for providing the same with a suitable counterbalancing force. This counterbalancing force is used namely to decrease force required to open the door and also facilitate its closing.
Also known in the art are two main types of rolling door assemblies, namely “dead shaft” rolling door assemblies and “live shaft” rolling door assemblies.
A “dead shaft” rolling door assembly is one in which, after proper installation thereof, the overhead shaft is securely fixed and tightened onto the fixed structure by means of brackets and corresponding fasteners, and thus does not rotate during normal operation of the rolling door assembly. In contrast, a “live shaft” rolling door assembly is one in which, after proper installation thereof, the overhead shaft is pivotally connected to the fixed structure and rotates thereabout during normal operation of the rolling door assembly.
In the case of a “dead shaft” rolling door assembly, the drum is pivotally mounted about the overhead shaft and rotates thereabout, and each counterbalancing spring typically has first and second ends operatively connected to the shaft and drum respectively so as to be wound and unwound accordingly, depending on the operation of the door assembly, so as to provide a corresponding counterbalancing force thereto.
In the case of a “live shaft” rolling door assembly, the drum is securely mounted about the overhead shaft and rotatable therewith with respect to the fixed structure, and each counterbalancing spring typically has first and second ends operatively connected to the shaft (or drum) and fixed structure respectively so as to be wound and unwound accordingly, depending on the operation of the door assembly, so as to provide a corresponding counterbalancing force thereto.
It is also known in the art that with “live shaft” rolling door assemblies for example, the winding thereof needs to be properly calibrated in order to ensure a suitable operation of the door assembly. Typically, an installer must use a winding system having a portion which cooperates with the fixed structure onto which a corresponding end of the counterbalancing spring of the assembly is operatively connected, said portion having corresponding sockets for receiving a winding bar. The aforementioned portion of the winding system is rotated by the installer with the winding bar inserted into a corresponding socket in order to provide the counterbalancing spring with a suitable torque, such that the latter may offer a corresponding suitable counterbalancing force. A problem associated with this type of winding is that it is carried out at elevated heights, typically using a ladder, given the fact that the overhead shafts of rolling door assemblies are generally located well above ground level or well out of human reach. Another problem associated with this type of winding is that is it difficult to achieve a precise winding because the winding of the assembly results from a rough estimate of the installer manually operating the winding bar, which is used as a lever arm for winding the assembly. Another problem associated with the above-mentioned type or winding is that a considerable effort is required from the installer to carry out the above-mentioned maneuvers, often causing him to force onto the parts and causing him also to undertake very precarious movements and/or positions, which is undesirable. Another problem associated with the above-mentioned conventional winding system is that it is not provided with a safety device which would prevent the rolling door assembly and/or the winding (or “counterbalancing”) thereof from being inadvertently tampered with.
Hence, in light of the aforementioned, there is a need for an improved system and/or method for winding a rolling door assembly which would be able to overcome some of the aforementioned problems.